[llvm] [ReachingDefAnalysis] Extend the analysis to stack objects. (PR #118097)

[Craig Topper via llvm-commits]

================
@@ -54,6 +71,11 @@ void ReachingDefAnalysis::enterBasicBlock(MachineBasicBlock *MBB) {
          "Unexpected basic block number.");
   MBBReachingDefs.startBasicBlock(MBBNumber, NumRegUnits);
 
+  MBBFrameObjsReachingDefs[MBBNumber].resize(NumStackObjects);
----------------
topperc wrote:

Cab we do something like this to avoid the loop?

```
MBBFrameObjsReachingDefs[MBBNumber].resize(NumStackObjects, {-1})
```

or

```
MBBFrameObjsReachingDefs[MBBNumber].resize(NumStackObjects, std::vector({-1}))
````

https://github.com/llvm/llvm-project/pull/118097